Door glass ascent/descent systems include window regulators for moving door glasses of vehicles upward or downward. The door glass is moved upward by the window regulator for closing a window of a vehicular door. When the door glass is moved upward and then an upper edge of the door glass hits a run channel, the door glass is prevented from moving further upward. At this time, a load exceeding a threshold level is applied to the window regulator. Such an excessive load is detected to thereby stop an operation of an electric motor with the result that the door glass stops at a closed position (i.e., at an uppermost position).
The above run channel is attached to a window sash of a front side door, as disclosed in, for example, JP-A-2003-72383.
The disclosed run channel has a U-shaped cross-sectional configuration formed by an inner wall, an outer wall and a peak portion. Inner and outer lips extend from the inner and outer walls for sealing engagement with inner and outer surfaces of the door glass, respectively.
As for the run channel, a window regulator raises the door glass and thereby presses an upper edge of the door glass against the peak portion of the run channel. With the upper edge of the door glass thus pressed against the peak portion, the door glass is not raised any more and a load exceeding a threshold level is applied to the window regulator. Such an excessive load is detected to thereby stop an operation of an electric motor with the result that the door glass stops at a closed position (i.e., an uppermost position).
As for the run channel, a problem arises that the window regulator raises and strikes the upper edge of the door glass onto the peak portion of the run channel at a predetermined speed whereupon an unpleasant strike sound is produced.
There has been a demand for a run channel arranged to reduce a strike sound of the door glass when the door glass moves to the closed position.